Further Investigation of Conical Diffusers with Annular Injection

Abstract

A comprehensive investigation is made, for a wide range of incompressible flows, into the merits of annular injection as a means of obtaining a high-performance diffuser with short axial length. Results show that injection yields considerable improvements in both the quality of the discharging flow and the magnitude of the pressure recovery. Accordingly, the technique is strongly recommended when a short, high-performance diffuser is required and when a suitable secondary supply is available. Recommendations are also made regarding the optimum cone angle and the geometry of the injection slot.

Performance optimization for two-dimensional rectangular diffuser by momentum injection using computational fluid dynamics

“…They also redefined the coefficient of pressure recovery to account for the injection energy. Duggins et al [6] have shown that an axial annular jet is better than a tangential annular jet for conical diffusers. Boundary layer control by suction has been attempted by Ackeret [7] and Furuya et al [8] at the diffuser inlet and they have succeeded in achieving higher performance for wide-angled conical diffusers.…”